  {{#description}}
  # {{{.}}}
  {{/description}}
  module {{classname}}
    {{#oneOf}}
    {{#-first}}
    # List of class defined in oneOf (OpenAPI v3)
    def self.openapi_one_of
      [
    {{/-first}}
        :"{{{.}}}"{{^-last}},{{/-last}}
    {{#-last}}
      ]
    end

    {{/-last}}
    {{/oneOf}}
    {{#discriminator}}
    {{#propertyName}}
    # Discriminator's property name (OpenAPI v3)
    def self.openapi_discriminator_name
      :"{{{.}}}"
    end

    {{/propertyName}}
    {{#mappedModels}}
    {{#-first}}
    # Discriminator's mapping (OpenAPI v3)
    def self.openapi_discriminator_mapping
      {
    {{/-first}}
        :"{{{mappingName}}}" => :"{{{modelName}}}"{{^-last}},{{/-last}}
    {{#-last}}
      }
    end

    {{/-last}}
    {{/mappedModels}}
    {{/discriminator}}
    # Builds the object
    # @param [Mixed] Data to be matched against the list of oneOf items
    # @return [Object] Returns the model or the data itself
    def self.build(data)
    {{#discriminator}}
      discriminator_value = data[openapi_discriminator_name]
      return nil unless discriminator_value
    {{#mappedModels}}
    {{#-first}}

      klass = openapi_discriminator_mapping[discriminator_value.to_sym]
      return nil unless klass

      {{moduleName}}.const_get(klass).build_from_hash(data)
    {{/-first}}
    {{/mappedModels}}
    {{^mappedModels}}
      {{moduleName}}.const_get(discriminator_value).build_from_hash(data)
    {{/mappedModels}}
    {{/discriminator}}
    {{^discriminator}}
      # Go through the list of oneOf items and attempt to identify the appropriate one.
      # Note:
      # - We do not attempt to check whether exactly one item matches.
      # - No advanced validation of types in some cases (e.g. "x: { type: string }" will happily match { x: 123 })
      #   due to the way the deserialization is made in the base_object template (it just casts without verifying).
      # - TODO: scalar values are de facto behaving as if they were nullable.
      # - TODO: logging when debugging is set.
      openapi_one_of.each do |klass|
        begin
          next if klass == :AnyType # "nullable: true"
          typed_data = find_and_cast_into_type(klass, data)
          return typed_data if typed_data
        rescue # rescue all errors so we keep iterating even if the current item lookup raises
        end
      end

      openapi_one_of.includes?(:AnyType) ? data : nil
    {{/discriminator}}
    end
    {{^discriminator}}

    SchemaMismatchError = Class.new(StandardError)

    # Note: 'File' is missing here because in the regular case we get the data _after_ a call to JSON.parse.
    private def self.find_and_cast_into_type(klass, data)
      return if data.nil?

      begin
        case klass.to_s
        when "Boolean"
          return data if data.instance_of?(TrueClass) || data.instance_of?(FalseClass)
        when "Float"
          return data if data.instance_of?(Float)
        when "Integer"
          return data if data.instance_of?(Integer)
        when "Time"
          return Time.parse(data)
        when "Date"
          return Date.parse(data)
        when "String"
          return data if data.instance_of?(String)
        when "Object" # "type: object"
          return data if data.instance_of?(Hash)
        when /\AArray<(?<sub_type>.+)>\z/ # "type: array"
          if data.instance_of?(Array)
            sub_type = Regexp.last_match[:sub_type]
            return data.map { |item| find_and_cast_into_type(sub_type, item) }
          end
        when /\AHash<String, (?<sub_type>.+)>\z/ # "type: object" with "additionalProperties: { ... }"
          if data.instance_of?(Hash) && data.keys.all? { |k| k.instance_of?(Symbol) || k.instance_of?(String) }
            sub_type = Regexp.last_match[:sub_type]
            return data.each_with_object({} of String | Symbol => Bool | Float | Integer | Time | Date | String | Array | Hash) { |(k, v), hsh| hsh[k] = find_and_cast_into_type(sub_type, v) }
          end
        else # model
          const = {{moduleName}}.const_get(klass)
          if const
            if const.respond_to?(:openapi_one_of) # nested oneOf model
              model = const.build(data)
              return model if model
            else
              # raise if data contains keys that are not known to the model
              raise unless (data.keys - const.acceptable_attributes).empty?
              model = const.build_from_hash(data)
              return model if model && model.valid?
            end
          end
        end

        raise # if no match by now, raise
      rescue
        raise SchemaMismatchError, "#{data} doesn't match the #{klass} type"
      end
    end
    {{/discriminator}}
  end
